According to the prior art, in cardboard box assembly machines, there is a cardboard sheet feeding mechanism, that comprises a series of vacuum suction elements (suction pads) which by means of an up and down movement, supply the assembly machine with sheets in a unitary manner.
The suction pads of these mechanisms are in a stable position. In order to modify their position, in the event of a change of format or dimensions of the cardboard sheet, it is necessary to stop the machine, so that the operator may have access to the mechanism and make the corrections and adjustment of operation of the suction pads by hand.
Although this operation is known to be simple, it takes up a long time, especially in the cases in which there are many suction pads assembled.
It is also noteworthy the series of mechanical tests and subsequent stopping of the machine to effect the exact adjustment of positioning of the suction pads.
In order to lift the laps that comprise the cardboard sheets, the known technique uses some tongues situated at the passage of the cardboard sheets in the feed path to the machine, whose tongues have a certain incline, in accordance with the type of box to be assembled, In other words, the laps are lifted and subjected to the action of the assembly mold directly.
With this certain difficulties are created regarding the operation of the glueing machines, due to the fact that the laps do not have a constant angulation position.